adde test for ApplicationTypeGet() and request with a tenant

usually it is not needet to include a tenant to the request but
it is expected that it will work with or without a tenant

application_type_handlers_test.go

@@ -307,7 +307,7 @@ func TestApplicationTypeList(t *testing.T) {
 }
 
 // TestApplicationTypeListWithTenant tests that list of application types is returned
-// even when tenant is provided (this request doesn't need a tenant)
+// even when tenant is provided (the request usually doesn't need a tenant)
 func TestApplicationTypeListWithTenant(t *testing.T) {
 	tenantId := int64(1)
 	c, rec := request.CreateTestContext(
@@ -318,7 +318,7 @@ func TestApplicationTypeListWithTenant(t *testing.T) {
 			"limit":   100,
 			"offset":  0,
 			"filters": []util.Filter{},
-			"tenant": tenantId,
+			"tenant":  tenantId,
 		},
 	)
 
@@ -388,6 +388,42 @@ func TestApplicationTypeGet(t *testing.T) {
 	}
 }
 
+// TestApplicationTypeGetWithTenant tests that application type is returned
+// even when tenant is provided (the request usually doesn't need a tenant)
+func TestApplicationTypeGetWithTenant(t *testing.T) {
+	tenantId := int64(1)
+	c, rec := request.CreateTestContext(
+		http.MethodGet,
+		"/api/sources/v3.1/application_types/1",
+		nil,
+		map[string]interface{}{
+			"tenant": tenantId,
+		},
+	)
+
+	c.SetParamNames("id")
+	c.SetParamValues("1")
+
+	err := ApplicationTypeGet(c)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if rec.Code != 200 {
+		t.Error("Did not return 200")
+	}
+
+	var outAppType m.ApplicationTypeResponse
+	err = json.Unmarshal(rec.Body.Bytes(), &outAppType)
+	if err != nil {
+		t.Error("Failed unmarshaling output")
+	}
+
+	if outAppType.DisplayName != "test app type" {
+		t.Error("ghosts infected the return")
+	}
+}
+
 func TestApplicationTypeGetNotFound(t *testing.T) {
 	c, rec := request.CreateTestContext(
 		http.MethodGet,